"Qualified" . "SOUND PRESSURE LEVEL" . "SOUND PRESSURE LEVEL" . "RDS386954" . "Lp = ln (p/p0) = ln 10.lg (p/p0) where p is the root-mean-square value of the sound pressure and the reference pressure p0 is equal to 20 muPa" . "u82237" . "2001.10.12" . .